Function to hide/unhide non adjacent columns

Question

I would like to create a function to hide/unhide non adjacent columns

I've tried that code (I4ve copied/paste from the forum) but as I don't understand what "hide=>" for example, I'm lost. Is it a variable?

Thanks if you could help me

function myFunction() {
  //list of columns that I want to hide/unhide
  const hideColumns = [0,1,3,7,15];

  const ss = SpreadsheetApp.getActiveSpreadsheet();
  const sheet = ss.getActiveSheet();
  const requests = [];
  
  // Create request for hiding/unhiding the hide columns.
  if (hideColumns.length > 0) {
    //unhidding hidden columns
    hideColumns.forEach(show=>{
    sheet.showColumn(sheet.getRange(1,show));
    sheet.getRange(11,1).activate();
  }
  }
  else {
    //hiddenning columns
    hideColumns.forEach(hide=>{
    sheet.hideColumn(sheet.getRange(1,hide));
    })
  }
}

Answer 1

When you use foreach loop for hideColumns array

show=>

Means the current element of array in loop.

It means you give a name of that element in array for loop.

Example;

    hideColumns.forEach(value=>{
  
      sheet.hideColumn(sheet.getRange(1,value)); // as you can see we used "value" in here to represent the elements in loop.
    })

Other example;

We have an array named "numbers" and there are numbers in it. We want to get all numbers and do something for everynumber such as printing or logging to console.

numbers.forEach(number => console.log(number))

You should look for arrays and loops to understand better.